Natalie Mayeaux squealed with delight and laughed as she ran from a large spider to skulls and pumpkins placed around her grandmother's yard in Bossier City.

Under 26 pounds and 37 inches tall, the 4-year-old barely hits the bottom of normal for her age on the growth chart, a feat she achieved after being placed on growth hormone therapy for about two years.

But although small, she's still only 10 inches shorter than her older brother Jacob, who is 8.

"He was always on the bottom of the growth curve, too. But doctors said he'd be fine," said Tammy Mayeaux, mother of Natalie and Jacob, who have growth disorders. "It was through Natalie we saw Jacob needed help, too. I was a first-time mother. If I'd known more, I might have been more determined to get him help sooner."

The Northwest Louisiana Walk for MAGIC on Saturday will shine a light on growth disorders, which may go undetected for years, according to the MAGIC (Major Aspects of Growth In Children) Foundation, the nonprofit that will benefit from the event.

Local nonprofit Families Helping Families in Shreveport is sponsoring the walk, which will begin at 10 a.m. at Betty Virginia Park in Shreveport. The course is a 5K (3.1-mile) loop around the park.

Participants are encouraged to collect additional donations. The money raised goes to aid in research and advocacy for more than 100 rare disorders affecting children's growth.

Mayeaux, who is helping organize the event, has learned you can't be afraid of your child's disability.

"It's hard at times, but mostly it's been a blessing. It's opened our eyes to other children with disabilities, and we've met so many people. Our family has come out with a new look on life."

Natalie was born weighing 1 pound, 13 ounces, measuring 13 inches long at 32 weeks and was diagnosed broadly with intrauterine growth retardation, small for gestational age, failure to thrive and gastroesophageal reflux disease.

But after several months of being on a feeding tube and different medications, the tiny infant was still not growing.

"Natalie's home health nurse and I felt something else must be going on and we began to research. That's when she found Russell-Silver Syndrome," Mayeaux said of the rare genetic disorder that is characterized by growth delays before birth and that includes a number of physical and developmental characteristics. "It fit Natalie to a T, and we took her to a geneticist (who) confirmed it."

After the diagnosis, Mayeaux also found the MAGIC Foundation, which has its home base in Illinois.

"It's been awesome just to have the support of other families," Mayeaux said. "We write to each other every day on a list serve; and every year they have a medical convention in Chicago."

The first year of Natalie's diagnosis, the Mayeauxs' church, Barksdale United Methodist, helped the family attend the convention.

"It's great for the kids; they see other kids just like them," Mayeaux said. "Most of them have feeding tubes. And they can compare their buttons and parents can compare what's going on with their child and learn about research."

Soon Mayeaux began demanding doctors give some attention to Jacob, too. He ultimately was diagnosed with Idiopathic Short Stature after being referred to a pediatric endocrinologist. Jacob recently began taking growth hormone, about the same time Natalie's therapy had to stop.

"The insurance company denied authorization because there wasn't enough studies that showed it was effective with RSS children," said Mayeaux, adding the therapy costs about $600 a vile and most children take three viles a month for many years.

"They denied Jacob, too. But Genetech (manufacturer of the growth hormone) has graciously given it to us while we wait on an appeal."

The family also is trying to appeal the decision for Natalie, whose growth spurt — 9 inches in two years — has come to a halt since being taken off the growth hormone.

It's been a learning curve for the Mayeauxs. They hope giving information about their family and the MAGIC Foundation can help other parents.

"So many people in our area have children (who) have growth issues but don't realize the effect it can have on them," Mayeaux said. "People need to be aware of the signs to look for in growth disorders and when to see a doctor."